1. Field of the Invention
The present invention relates to a vibration wave motor for performing linear drive using a ultrasonic wave vibrator, and more particularly, relates to a vibration motor miniaturized by employing a simple structure.
2. Description of the Related Art
Recently the ultrasonic wave motor (vibration wave motor) is observed, as a new motor to be replacing the electromagnetic motor.
Compared with a conventional electromagnetic motor such a ultrasonic wave motor offers the following advantages.    (1) Low-speed high-driving force can be obtained without any gearing.    (2) It has a large holding force.    (3) It has a long stroke and high resolution.    (4) It operates quietly.    (5) It causes no magnetic noise and is also not affected by noise.
As a conventional ultrasonic wave motor having such advantages, a linear ultrasonic wave motor whose moving part is provided with two vibrator plates, in which one guide shaft is inserted between each pair of opposed projected parts formed on the opposed surfaces of each vibrator plate and whose moving part moves along the guide shaft as a result of the vibration of the two vibrator plates is proposed (for example, see Japanese Patent Application No. H09-051687, paragraphs [0011]-[0012] and FIG. 1).